SovietRxiv · Open Access in English
Rediscovering the Soviet scientific archive, in English
25357 full-text translations 14926 English PDFs 22539 abstracts
Showing 50 of 25357 papers
This paper evaluates the newly identified Alguy deposit as a potential source of low-iron talc for ceramic applications, in the context of limited domestic supplies of high-quality talc. Three representative samples were examined by grain-size, chemical, petrographic, X-ray diffraction, thermal, and…
This paper evaluates rock from the Burenichevskoye deposit near Kemerovo as a single-component raw material for ceramic floor tiles. Using mineralogical, granulometric, chemical, and standard ceramic testing, the authors characterize its hydromica-rich composition, firing behavior, molding propertie…
The paper examines the diffusional descending branch of the anodic peak in amalgam polarography with accumulation on a stationary mercury drop electrode, a feature that can distort closely spaced peaks and reduce resolution. By solving Fick’s second equation for spherical diffusion in a finite mercu…
This study examines how background solution volume and preliminary electrolysis time affect anodic peak heights in accumulation amalgam polarography for gallium and germanium, with lead used as a reference system. Experiments at micromolar concentrations varied solution volume, electrolysis duration…
The study examines the amalgam polarographic behavior of gallium in several supporting electrolytes, including potassium chloride, potassium nitrate, sodium chloride, acetate buffer, potassium thiocyanate, and potassium chloride with sodium salicylate. Using anodic and cathodic polarograms after pre…
This paper examines how the viscosity of binary regular solutions depends on composition and on the molecular weight of the dissolved component, using Stromberg’s theory of mixture viscosity. It derives criteria for regular systems, including symmetry of viscosity deviations from additivity about th…
This paper experimentally examines the anodic peak constant for amalgam polarography with accumulation at a stationary mercury film electrode. Using theoretical relations for reversible processes and measurements for Tl, Cd, Cu, Pb, Zn, Bi, and In in several supporting electrolytes, it determines va…
This study examines polarographic characteristics of anodic peaks in amalgam polarography with accumulation and evaluates their use for comparing sensitivity and electrode-process reversibility. Cathodic and anodic peaks were measured for several elements, including copper, lead, cadmium, zinc, thal…
This paper develops a theoretical expression for fully irreversible anodic peaks at a stationary amalgam film electrode under low potential scan rates. Assuming a thin mercury film with uniform metal concentration throughout dissolution and neglecting the reverse electrode process, the authors deriv…
This study examines ultramicroconcentrations of indium and cadmium in a nonaqueous silicon tetrachloride, n-propyl alcohol mixture using amalgam polarography with accumulation, with comparisons to aqueous supporting media. The authors show that partial neutralization with pyridine shifts the hydroge…
This study examines how ammonia concentration affects irreversible anodic and cathodic processes in the Zn(Hg), Zn(II), NH3 system under linearly varying potential. Using a mercury film electrode and comparing the results with dropping mercury or amalgam electrode polarography, the authors measured …
This text presents a table of contents for an issue covering mathematical physics, physics, technical physics, geophysics, and crystallography, with article titles and page numbers. It also includes corrections to previously published papers by V. R. Portnov and M. A. Naimark, specifying formula cha…
This paper reports the artificial synthesis of large spherical polycrystalline diamond specimens closely resembling natural ballas, a rare diamond form not previously obtained in reported synthetic diamond work. The authors describe specimens approximately 6 to 6.5 mm in diameter, examine their dens…
This paper examines the origin of anomalous visible-light scattering in submicron-inhomogeneous sodium silicate and sodium borosilicate glasses, especially wavelength exponents greater than the Rayleigh value and backward-elongated scattering indicatrices. The authors compare two explanations, inter…
This note studies solvability of nonlinear operator equations of the form AF(x) = x in a real Hilbert space, relaxing earlier assumptions that the positive self-adjoint operator A be bounded. It establishes existence theorems for potential nonlinear operators under weak upper semicontinuity and coer…
This paper studies finite-dimensional subspaces of continuous functions on an interval, focusing on Chebyshev systems, bounded oscillation, and several notions of suitability defined by the realizability of prescribed alternating extrema. It formulates these properties topologically in terms of func…
This paper examines the displacement of a rigid sphere immersed in an ideal compressible fluid under the action of an acoustic pressure shock wave. Building on earlier expressions for reflected and radiated wave potentials near curved bodies, it formulates the sphere’s equation of motion and compare…
The paper studies unitary extensions of isometric operators in the Pontryagin space with one negative square and applies these results to extension problems for nondegenerate finite Toeplitz sequences in the class with one positive square. It gives geometric criteria for bounded, continuously invert…
The paper develops a family of integral constructions for bounded functions on an interval, using modified upper and lower sums defined through outer Lebesgue measure and a parameter controlling exceptional subsets. It proves that for fixed positive parameter these sums converge to Lebesgue integral…
An existence theorem for an optimal control that minimizes the functional $J(u)=\Phi(x(t_1))$ on the trajectories of the system $$\dot{x}(t)=f(x(t),x(t-h(x(t),u(t),t)),u(t),t),\quad x(\tau)=\varphi(\tau),\quad\tau\in S_0.$$ is proved. Bibliography: 5 items.
This paper estimates terrestrial heat flow and radiogenic heat generation in the Epigercynian platform structures of lowland Northern Dagestan using deep well temperature gradients, laboratory thermal-conductivity measurements, and gamma-spectrometric determinations of uranium, thorium, and potassiu…
The paper addresses Aleksandrov’s problem on the existence of universal extremally disconnected bicompacta of a given weight and Antonovskii’s question on extremally disconnected bicompacta homogeneous with respect to character. Using the theory of absolutes, irreducible perfect mappings, and cardin…
The paper studies rectilinear stationary and nonstationary motions of an ideally plastic medium using variational formulations. For stationary pipe flow and for cylinders moving in a plastic medium, it analyzes the minimization of a nonreflexive, nonstrictly convex functional and shows that below cr…
The paper formulates a general probabilistic definition of stability for the functioning of complex systems described by random processes and parameterized families of functionals. By varying the classes of admissible parameter sets, target function sets, inclusion types, and probability thresholds,…
This note derives a priori estimates for the principal radii of curvature of a closed convex surface satisfying an equation of the form f(R1, R2) = phi(n), where f is twice differentiable and strictly increasing in both curvature radii. Using the support function and local coordinates at points wher…
This paper studies sufficient conditions for an absolute minimum in an optimal control problem with endpoint constraints, state dependent control sets, and a Bolza type functional. It develops a generalized auxiliary functional method based on a lemma comparing minimization over the admissible class…
This paper formulates a statistical description of turbulence using the vorticity field as the basic variable for an incompressible viscous fluid. Starting from the hydrodynamic equations, it derives kinetic chains for Lagrangian multiparticle distribution densities and for Eulerian multipoint vorti…
This paper develops a cover-based method for factoring continuous mappings while controlling weight and dimension, presented as an alternative to spectral techniques. It first reproves Mardešić’s factorization theorem for mappings of bicompacta, then formalizes refinement operations on families of c…
A solution $x(t,\lambda)$ is called a singular solution of the operator equation $x(t)=\lambda P(x(t))$ if $x(t,\lambda)\to\infty$ for $\lambda\to0$. Using the example of the equation $$\begin{aligned}\dot{x}(t)&=\lambda\int_0^1[A_1(t,s)x(s-\tau)+A_2(t,s)\dot{x}(s-\tau)+A_3(t,s)x^2(s)]\,ds+\\&\lambd…
A representation of Hertz vectors (electric or magnetic) and their corresponding electromagnetic fields $\mathbf E$ and $\mathbf H$, generated by arbitrarily oriented dipoles (electric or magnetic, respectively) in the presence of a perfectly conducting half-plane, has been obtained in terms of Macd…
This note studies the existence and multiplicity of square roots of measure-preserving automorphisms, with emphasis on transformations having continuous or simple spectrum. Using cyclic approximation by periodic transformations and skew products with fiber of order two, it constructs an automorphism…
This study examines nonstationary current flow in metal, dielectric, metal structures using single crystal cadmium sulfide samples with indium electrodes. Measurements of time dependent current, current voltage characteristics, and discharge current show that below a threshold voltage the current de…
This note studies a class of degenerate quasilinear elliptic equations and systems of arbitrary order with homogeneous first boundary conditions in a bounded smooth domain. Under differentiability, monotonicity-type degeneracy, and Lipschitz-like assumptions on the nonlinear coefficients, it formula…
The note formulates generalizations of Grobman and Hartman results on the topological equivalence of nonlinear systems of the form x dot equals Ax plus F(x) and their linear parts, under hyperbolicity of the matrix A. It introduces H-homeomorphisms and A-homeomorphisms with bounded displacement, the…
A plane chain model is developed for the reflection of fast argon ions from a copper single crystal at grazing incidence, focusing on successive collisions with atoms in a surface chain. The calculation follows elastic and inelastic energy losses over several small-angle and large-angle deflections,…
The paper examines the divergences of vector and axial currents in the presence of electromagnetic and weak interactions, motivated by the relation between current algebra and proposed divergence hypotheses. Using a quark model with minimal electromagnetic coupling, universal weak interactions, and …
This paper proves a weighted \(L_2\) estimate for generalized derivatives near the boundary of a smooth domain, motivated by earlier boundary growth estimates for solutions of elliptic equations. Starting from a known inequality that bounds higher weighted derivative norms by a finite sum of lower o…
This paper develops a statistical description of seismic wave propagation in weakly inhomogeneous real media, where small fluctuations of elastic parameters scatter energy from the deterministic wave field into a random component. It introduces a seismic turbidity coefficient, defined through the gr…
The paper studies conditions under which representations of semisimple Lie algebras over fields of characteristic zero remain completely reducible in infinite-dimensional spaces. It adapts the standard finite-dimensional proof by isolating the role of Whitehead’s lemma and proves complete reducibili…
This paper studies dense increasing sequences of integers for which the equation defining a greatest common divisor, gcd(ai, aj) = ar with r < i < j, has no solutions. Contrasting this problem with the corresponding least common multiple equation considered in earlier work, the authors prove that an…
This paper studies extension problems for continuous, theta-continuous, and delta-continuous mappings between Hausdorff topological spaces, especially in relation to H-closed extensions and paracombinatorial extensions. It proves that every perfect continuous onto mapping extends from a Hausdorff sp…
This note studies regularity of generalized solutions of linear partial differential equations with constant coefficients in domains containing unbounded Euclidean directions, under assumptions that selected derivatives are square integrable and decrease at infinity in an appropriate local sense. Us…
This note studies a nonlinear mixed problem for the string equation when the usual nondegeneracy condition at a boundary fails at a finite time during continuation of a smooth solution. It analyzes the limiting behavior at the critical time and proves that, depending on associated boundary quantitie…
This note studies ranks of elliptic curves over rational function fields over finite fields, with the aim of producing examples of arbitrarily large rank over a fixed field. Using Tate’s relation between rational points over a function field and homomorphisms from a Jacobian, the authors compute zet…
This paper analyzes how radiation damping changes the angular and energy distribution of an ultrarelativistic charged particle flux passing through a plane parallel layer of uniform magnetic field. Using the damping law for transverse velocity and a finite traversal time set by the longitudinal velo…
